In all the chapters the Case Studies represent situations similar to those that the medical assistant may encounter in daily practice. Students are encouraged to consider the case study as they read each chapter.

Five days ago, a 40-year-old woman came to the doctor's office where you work as a medical assistant. She complained about pain in her back and right leg. Because this patient had a history of disc damage in her spine, she was sent home with pain medication and an order for bed rest for a 24-hour period. Two days later, she returned to the office with nausea, a severe headache, muscle twitching in her legs and arms, severe back pain, and tightness in her chest. The doctor once more asked the patient to elaborate on her activities the day before she fell ill. He was told that she had sprayed her furniture and carpets with an organophosphate insecticide to get rid of fleas in her house. She had also dipped her cats and dogs with the same insecticide. The doctor explained that organophosphates block acetylcholinesterase and immediately transferred her to the hospital for respiratory therapy and medicine to combat the insecticide poisoning.

As you read this chapter, consider the following questions:

1. What is the function of acetylcholinesterase?

2. Why does this patient exhibit muscle twitching and back pain?

3. What type of respiratory therapy will this patient require?

4. What precautions should a person take when using insecticides that contain organophosphates?

5. Why is it important for patients to give their doctor a complete account of their activities prior to an illness?